申请人:ENICHEM SYNTHESIS S.p.A.
公开号:EP0092102A1
公开(公告)日:1983-10-26
A process is described for preparing 2,3-dihydro-2,2-dimethylbenzofuran-7-ol (I), which is a useful intermediary in the preparation of Carbofuran, a known multi-functional insecticide.
The process consists essentially of reacting the pyrocatechol and a methallylhalide in an inert organic solvent in the presence of a solid inorganic base and a suitable catalyst, to obtain o·methallyloxyphenol with high conversion and high selectivity; this product is thermally transposed to o·methallylpyrocatechol, which is finally cyclised to the product (I) by heterogenous catalysis in the presence of solid acid catalysts.
All stages of the process can be carried out in a single reaction medium, without separating intermediate products.
本发明描述了一种制备 2,3-二氢-2,2-二甲基苯并呋喃-7-醇 (I) 的工艺,该物质是制备已知多功能杀虫剂克百威的有用中间体。
该工艺主要包括在惰性有机溶剂中,在固体无机碱和适当催化剂的存在下,使焦儿茶酚和甲烯丙基卤化物发生反应,从而获得高转化率和高选择性的邻甲烯丙基氧基苯酚;该产物经热转印为邻甲烯丙基邻苯二酚,最后在固体酸催化剂的存在下,通过异源催化环化为产物(I)。
该工艺的所有阶段均可在单一反应介质中进行,无需分离中间产物。